# Angular Acceleration

Comparison of the effects of inertia on (from back to front) a hollow spherical shell (red), a solid ball (orange), a ring (green), & a solid cylinder (blue). "An object's moment of inertia determines how much it resists rotational motion. In this simulation, four objects are placed on a ramp and left to roll without slipping. Starting from rest, each will experience an angular acceleration based on their moment of inertia." Caption from link. Click through for animation

Fastest-Spinning Man-Made Object Created. The rotation rate is so fast that the angular acceleration at the sphere surface is 1 billion times that of gravity on the Earth surface — it's amazing that the centrifugal forces [the forces pushing outward due to circular motion] do not cause the sphere to disintegrate.

ROTATIONAL MOTION LECTURE SOFTWARE Rotational Motion is a software based lecture aid covering the following: the definition of radians and the conversion to degrees, the derivation and definition of angular velocity and angular acceleration, and the similarity of the linear and rotation motion equations. The lecture screens are set up in a step by step fashion and there are a number of simulations to help illustrate the fact that many of the variables are related.

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